A communication transmitted from Yi-An Huang, City Manager, relative to Potential amendments to required setbacks for additions and alterations to existing buildings in the Multifamily Housing Zoning Petitions

C I T Y O F C A M B R I D G E Community Development Department IRAM FAROOQ Assistant City Manager for Community Development SANDRA CLARKE Chief of Admin/Operations MELISSA PETERS Chief of Planning Strategy 344 Broadway Cambridge, MA 02139 Voice: [phone removed] Fax: [phone removed] TTY: [phone removed] www.cambridgema.gov To: Yi-An Huang, City Manager From: Iram Farooq, Assistant City Manager for Community Development Megan Bayer, City Solicitor Date: January 23, 2025 Subject: Potential amendments to required setbacks for additions and alterations to existing buildings in the Multifamily Housing Zoning Petitions At the January 16, 2025, meeting of the Ordinance Committee, members of the committee asked about setback requirements in the case of alterations and additions to existing buildings with non-conforming setbacks. It was suggested that flexibility could be provided for in these cases, along with other “contextual” flexibility that would help make existing buildings conforming and allow new development to fit existing setback patterns in neighborhoods. Below is a potential new paragraph “(c)” of footnote “(4)” in Section 5.40 that would treat existing setbacks as conforming in the case of additions and alterations to existing buildings, and permit vertical additions to align with existing walls if they are within the required setback. (4) The required side or rear yard setback may be reduced in either of the ways described below: (a) No side or rear yard setback shall be required for a building or portion thereof that directly abuts a building or portion thereof on an adjacent lot, as in the case of semi-detached dwellings or other adjoining buildings that share a party wall. However, portions of the building that do not directly abut portions of the building on an adjacent lot shall conform to the required side or rear yard setback. (b) The required setback for one side yard of a lot may be reduced if the setbacks for two opposite side yards of the lot sum to at least 10 feet, and if no portion of a building is closer than 10 feet to the exterior wall of an existing building on an abutting lot. (c) In the case of an alteration or addition to a building in existence since on or before January 1, 2025, the required side and rear yard setback distances shall be those of the existing building or structure. Additions or alterations that extend horizontally beyond the vertical walls of the existing building shall conform to the requirements in Table 5-1, as modified by paragraphs (a) and (b) above.